Medium
d.35 on Vaillant ecoTEC plus Aquaplus

Your boiler is struggling to switch between heating your house and heating your hot water taps, which may cause one of these services to stop working correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Diverter valve position

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.22View →

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